Tool-holder



0. CRONAU.

TOOL HOLDER- APPLICATION FILED JULY 29,19l9. 1,341,206. Patented y 25,1920.

ATTO NE! OTTO CRONAU, OF NEW YORK, N. Y.

TOOL-HOLDER.

Specification of Letters Patent.

Patented May 25, 1920.

Application filed July 29, 1919. Serial No. 314,076.

I '0 all whom it may concern:

Be .it known that I, Orro CRONAU, a citizen of Germany, and a residentof the borough of Manhattan, city, county, and State of New York, haveinvented certain new and useful Improvements in Tool-Holders, of whichthe following is a specification.

This invention relates to tool holders and has for its primary object toprovide an im' proved mounting of the cutting bits in a double actingplaner and shaper whereby the bits alternately engage and operate uponthe work as the holder is moved in opposite directions.

It is a more particular object of my in vention to provide a tool holderof the above character having pivotally mounted members in which thecutting bits are respectively secured, and a non-yielding positiveconnection; between said members whereby they are automaticallyoscillated in unison,

and one of the cutting bits moved. into operative engagement with thework as the other bit is moved out of such engagement, upon a reversalof the rectilinear movement of the tool holder.

The invention further contemplates a very simple and compact arrangementof the several parts of my improved tool holder, resulting in a strongand durable construction which is not liable to easily get out of orderor require frequent repair.

Having the aforementioned objects in view, the present inventioncomprehends certain novel and improved combinations of mechanicalelements, and the structural characteristics thereof, as will be morefully developed inthe following description and subsequentlyincorporated in the subjoined claims.

In the accompanying drawing, wherein I have illustrated one practicalembodiment of my invention and in which similar ref erence charactersdesignate corresponding parts throughout the several views,

Figure 1 is a side elevation of the tool holder, one side of the bodybeing broken away;

Fig. 2 is an elevation at right angles to Fig.- 1; and

ig. 3 is a detail fragmentary section of the Work piece illustrating thecutting action of the tool hits.

Referring in detail to the drawin 5 designates the body of the toolholder w ich is in the form of a single metal casting having parallel.side flanges 6. A rectangular shank T is formed integral with this bodycasting at one of its ends and is adapted to be suitably mounted in. acarriage or other reciprocating part of the planer or shaping machine.

Between the parallel flanges 6, the tool bit carrying members 8 arearranged, said members being loosely mounted upon the shafts 9 foroscillatory movement, the ends of said shafts being fixed in the sideflanges (3 of the body 5. Each of the members 8 is provided with anobliquely extending rectangular opening 10 to receive the shank of atool. bit 1].. These tool bits may be adjustably fixed in the openings10 with their cutting points projecting the desired distance below thelower ends of the members 8 by means of the set screws 12 which arethreaded in bosses 13 formed upon the members 8.

At their upper ends and at the inner sides thereof, the members 8 areconnected to each other by means of a rigid link bar H, the ends of thelink bar fitting loosely in slots or bifurcations formed in the respective tool carrying members 8 and being loosely engaged. upon thetransverse pivot pins 15 which are fixed in said members. Each member 8is further provided on its upper end. with a shoulder l6which is adaptedto abut against the horizontal wall of the body 5 and thus limit thepivotal movement of said members in one direction.

In the operation of my improved tool holder as above described, duringthe movement of the holder to the right as seen in F .ig. 1, the pointof the left hand cutting bit 11 is engaged with the work piece and.makes a roughing out indicated at V in. Fig. 3 of the drawing. Duringthis operation of the left hand cutting bit, it will be observed thatthe pressure of the bit upon the work piece tends to rock the memher 8in which the bit is mounted upon the pivot shaft 9, and hold theshoulder 16 there of in close contact with the body 5. Through themedium of the link 14:, the other of the members 8 is rocked upon itsshaft 9 and .in a reverse direction to the movement of the member 8first referred to, so that the other of the cutting bits 11 at the rightwill be held in an elevated position and out of contact with the surfaceof the work piece. WVhen the reciprocating movement of the tool isreversed and pressure upon the point of the left hand cutting bit 11 isrelieved, the member 8 in which the bit is mounted oscillates upon itspivot shaft 9 and, this bit is lifted from contact with the work piecewhile simultaneously, through the medium of the link 14:, the right handmember 8 is rocked upon its pivot shaft and the tool bit carried by saidmember is lowered into operative engagement with the work piece. Thistool bit, as the holder is moved to the left, operates upon the roughcut surface previously formed and makes a finished surface on the workpiece as shown at V These cutting or planing operations are repeated adin/im'tum in the reciprocation of the tool holder until the entiresurface of the work piece has been operated upon and provided with afinished surface.

It will be apparent that my improved tool holder provides a doubleacting metal planer or shaper which will bevery positive and reliable inpractical operation. No manual adjustments whatever are required, butthe movement of the cutting bits from their active to inactive positionsat the end of each operating stroke of the holder occurs instantaneouslyand automatically. When one cutting bit is in action, the point of theother bit does not drag upon the surface of the work piece, but issupported entirely out of contact therewith. Thus wear upon the hitpoints will be reduced to a minimum. The bit carrying members or blocks8 are very compactly arranged and associated with the body of the toolholder and are operatively connected by means of a single rigid linkbar. I have therefore succeeded in producing a construction whereinsprings or other easily breakable parts are dispensed with so that thedevice as a whole, will be durable and serviceable in practical use andnot liable to get out of order. It will be apparent of course, that theimproved tool holder may be constructed in various sizes, and that thebody of the holder as well as the bit carrying blocks or members 8 maybe otherwise shaped and proportioned than as indicated in theaccompanying drawing.

In the preceding description and the ac eompanying drawing, I havedisclosed one practical embodiment of the invention, which, however, maylikewise be exemplified in numerous alternative constructions.Accordingly the invention as herein claimed is to be considered asinclusive of all legitimate equivalents for the various elementsemployed as well as other'contemplated arrangements thereof, which maysatisfactorily accomplish the desired results.

I claim:

.1. A tool holder of the character described, including a body, opposedoscillatable members mounted on said body and. having their pivotalcenters laterally spaced from each other, a cutting bit carried by or chof said members, and a non-yieldable connection between thebit carryingmembers to cause the unitary oscillation of said members and disengageone of the cutting bits from the work simultaneously with the engagementof the other cutting bit therewith when the reciprocating movement ofthe holder is reversed.

2. A tool holder of the character described, including a body, opposedoscillatable members mounted on said body, a cutting bit carried by eachof said members, and a rigid link connection between the bit carryingmembers to cause the unitary os' cillation of said members and disengageone of the cutting bits from the work simultaneously with the engagementof the other cutting bit therewith when the reciprocating movement ofthe holder is reversed.

3. A tool holder of the character described, including a body, opposedoscillatable members mounted on said body, a cutting bit carried by eachof said members, and a single rigid link pivotally connected at its endsto said members in spaced relation to the pivotal centers thereof,between the bit carrying members to cause the unitary oscillation ofsaid members and disengage one of the cutting bits from the worksimultaneously with the engagement of the other cutting bit therewithwhen the reciprocating movement of the holder is re versed.

A tool holder of the character described, including a body member havingspaced side flanges, members pivotally mounted between said side flangesfor oscillatory movement and longitudinally spaced from each other, acutting bit carried by each of said members, and means disposed betwecnthe side flanges of the body member and connecting said bit carryingmembers to each other to cause simultaneous oscillation thereof andthereby disengage one cutting bit from the work and engage the othercutting bit therewith upon a reversal in the reciprocating movement ofthe tool holder.

5. A tool holder of the character described, including a body memberhaving spaced side flanges, members mounted between said side flangesfor oscillatory movement and longitudinally spaced from each other, acutting bit carried. by each of said members, and a single rigid linkextending longitudinally between said. side flanges of the body memberand pivotally connected at its ends to the spaced bit carrying membersto cause simultaneous oscillation thereof and thereby disengage onecutting bit from the work and engage the pivotally other cutting bittherewith upon a reversal in the reciprocating movement of the toolholder.

6. A holder of the cha'acter described including means for supportingspaced cut ting bits converging with relation to each other toward thesurface oi the work, and automatic means for simultaneously shifting thecutting bits in relatively opposite directions to operatively engage onebit with the work and disengage the other bit from the work surface inthe operation of the tool.

7. A tool holder of the character described including a body, opposedoscillatable members mounted on said body, a cutting bit carried by eachof said members, said bits converging toward their cutting points, andmeans connecting said members to each other and operating toautomatically transmit oscillating movement from one member to the otherand thereby alternately engage the cutting bits with the work when thereciprocating movement of the holder is reversed.

In testimony that I claim the foregoing as my invention, I have signedmy name hereunder.

OTTO CRONAU.

